1502 WALL ST IMAGINE CHILDRENS MUSEUM 2022-08-25

Gravel and Wire Mesh Filter Gravel and wire mesh filters are gravel barriers placed over the top of the inlet.This method does not provide an overflow. Design and installation specifications for gravel and wire mesh filters include: . Use a hardware cloth or comparable wire mesh with'/-inch openings. o Place wire mesh over the drop inlet so that the wire extends a minimum of 1-foot bey- ond each side of the inlet structure. • Overlap the strips if more than one strip of mesh is necessary. . Place coarse aggregate over the wire mesh. o Provide at least a 12-inch depth of aggregate over the entire inlet opening and extend at least 18-inches on all sides. Catch Basin Filters Catch basin filters are designed by manufacturers for construction sites.The limited sediment stor- age capacity increases the amount of inspection and maintenance required,which may be daily for heavy sediment loads.To reduce maintenance requirements, combine a catch basin filter with another type of inlet protection.This type of inlet protection provides flow bypass without overflow and therefore may be a better method for inlets located along active rights-of-way. Design and install- ation specifications for catch basin filters include: . Provides 5 cubic feet of storage. . Requires dewatering provisions. . Provides a high-flow bypass that will not clog under normal use at a construction site. . Insert the catch basin filter in the catch basin just below the grating. Curb Inlet Protection with Wooden Weir Curb inlet protection with wooden weir is an option that consists of a barrier formed around a curb inlet with a wooden frame and gravel. Design and installation specifications for curb inlet protection with wooden weirs include: . Use wire mesh with'/-inch openings. . Use extra strength filter cloth. . Construct a frame. . Attach the wire and filter fabric to the frame. . Pile coarse washed aggregate against the wire and fabric. . Place weight on the frame anchors. 2019 Stormwater Management Manual for Western Washington Volume II-Chapter 3-Page 360